Materials Data on NaMn4O8 by Materials Project
NaMn4O8 crystallizes in the monoclinic P2_1/c space group. The structure is three-dimensional. Na1+ is bonded in a 5-coordinate geometry to five O2- atoms. There are a spread of Na–O bond distances ranging from 2.41–2.67 Å. There are four inequivalent Mn+3.75+ sites. In the first Mn+3.75+ site, Mn+3.75+ is bonded to six O2- atoms to form a mixture of edge and corner-sharing MnO6 octahedra. The corner-sharing octahedra tilt angles range from 50–53°. There are a spread of Mn–O bond distances ranging from 1.92–1.98 Å. In the second Mn+3.75+ site, Mn+3.75+ is bonded to six O2- atoms to form a mixture of edge and corner-sharing MnO6 octahedra. The corner-sharing octahedra tilt angles range from 49–53°. There are a spread of Mn–O bond distances ranging from 1.92–2.04 Å. In the third Mn+3.75+ site, Mn+3.75+ is bonded to six O2- atoms to form a mixture of edge and corner-sharing MnO6 octahedra. The corner-sharing octahedra tilt angles range from 50–52°. There are a spread of Mn–O bond distances ranging from 1.91–2.03 Å. In the fourth Mn+3.75+ site, Mn+3.75+ is bonded to six O2- atoms to form a mixture of edge and corner-sharing MnO6 octahedra. The corner-sharing octahedra tilt angles range from 49–53°. There are a spread of Mn–O bond distances ranging from 1.93–2.00 Å. There are eight inequivalent O2- sites. In the first O2- site, O2- is bonded to one Na1+ and three Mn+3.75+ atoms to form a mixture of distorted edge and corner-sharing ONaMn3 trigonal pyramids. In the second O2- site, O2- is bonded to one Na1+ and three Mn+3.75+ atoms to form a mixture of distorted edge and corner-sharing ONaMn3 trigonal pyramids. In the third O2- site, O2- is bonded to one Na1+ and three Mn+3.75+ atoms to form a mixture of distorted edge and corner-sharing ONaMn3 trigonal pyramids. In the fourth O2- site, O2- is bonded to one Na1+ and three Mn+3.75+ atoms to form a mixture of distorted edge and corner-sharing ONaMn3 trigonal pyramids. In the fifth O2- site, O2- is bonded in a 4-coordinate geometry to one Na1+ and three Mn+3.75+ atoms. In the sixth O2- site, O2- is bonded in a distorted trigonal planar geometry to three Mn+3.75+ atoms. In the seventh O2- site, O2- is bonded in a trigonal planar geometry to three Mn+3.75+ atoms. In the eighth O2- site, O2- is bonded in a trigonal planar geometry to three Mn+3.75+ atoms.